Jean-Claude Juncker, who takes up the Commission presidency in November, also expressed his support for a target of 30% or more.

Current Commission president Manuel Barroso, on the other hand, favoured a target of 27% to 29%. He argued a higher target would undermine the emissions trading system – a market-based approach to cutting emissions through carbon pricing.

Marcus Ferdinand, head of EU carbon analysis at Thompson Reuters, explained: “A higher energy efficiency target would result in lower emissions. With lower emissions, European carbon prices would not incentivize the desired amount of abatement in the traded sectors. This bears the potential to downgrade the European carbon market from being the central pillar of European climate policy.”

According to Ferdinand’s projections, the 30% target will lead to an average carbon price of €15 a tonne between 2021 and 2030, 19% lower than under business as usual. This rises to €25/t if the Commission implements plans for a “market stability reserve” to combat an over-supply of carbon allowances.

He concluded: “The market stability reserve is outweighing by far the slightly bearish impact of the proposed energy efficiency target by supporting European carbon prices until the end of the next decade.”

For every 1% energy saving, the Commission estimates EU gas imports will decrease by 2.6%, helping with energy security.

The announcement also highlighted the potential for energy bill savings from lower consumption and to create business opportunities in construction and equipment manufacture.

As well as proposing a level of ambition for future energy savings, the Commission reviewed member states’ performance.

At current rates of progress, the EU will miss its non-binding 2020 target of 20%. It is on course to achieve 18% or 19%, but the Commission said it would “act decisively” to get the bloc back on track.

However it has succeeded in breaking the link between economic growth and energy consumption.

Energy consumption stayed roughly flat across Europe between 1995 and 2013 while GDP grew by 34%.

New buildings today use half the energy of those built in the 1980s, according to the Commission. Energy intensity of European industry fell 19% between 2001 and 2011.